Is it at all possible the stones were moved across ice? Or that they were moved by ice? Have they ruled that out?
http://brian-mountainman.blogspot.com.au/2013/11/spotted-dolerites-and-carn-goedog.html
Stonehenge and the Ice Age
How much do we know about Stonehenge? Less than we think. And what has Stonehenge got to do with the Ice Age? More than we might think. This blog is mostly devoted to the problems of where the Stonehenge bluestones came from, and how they got from their source areas to the monument. Now and then I will muse on related Stonehenge topics which have an Ice Age dimension...
If the climate had been cold enough, that might work, but alas, it wasn’t. There’s been a fairly steady drumbeat by a few that all the stones got to the site by glacial movements, IOW, they were just strewn around the general area, then 10000 years later someone came by and thought, how neat, let’s shape them just so and pile them up. :’)